Using A Computer To Simulate The Static Electric Filed

Applying the conception of flux lines to the theory of electromagnetic field makes abstract electrostatic field visible and intuitive. But due to the difficulties of the theoretical calculation and the limitation of the technique of image display, only some two-dimensional graphs of electromagnetic field of a planar set of point charges or symmetrically and uniformly charged bodies, which ignores the boundary effect, are introduced in the present electromagnetics teaching materials. For complicated uniformly charged bodies, the electric field lines and equipotential lines, especially their three-dimensional distributions are hard to be depicted, which brings much incovenience for the acquaintance of the electrostatic field.In this paper, on the basis of existing tracing method and differential coefficient method, five new methods are put forward, superposing of infinitesimal element-tangent method, differential coefficient-tangent method, equation method, slicing method and axonometric projection method, by taking advantage of fast calculating ability of the computer. Two-dimensional planar electrostatic field of complicated charged bodies are simulated successfully with these methods. The changing trend of electric field along a certain direction of a set of point charges and a graph of three-dimensional electrostatic field are also given in this paper.These methods can also be applied to the simulation of uniform magnetic field. A theoretic formula on how to change the geometrical shape of a magnet and augment the range of uniform magnetic field is brought forward in this paper by simulation.